铁道标准设计2025，Vol.69Issue(8)：1-11,11.DOI:10.13238/j.issn.1004-2954.202501210004
PE-ECC构件冻融循环后承载性能试验研究
Experimental Study on Load-Bearing Capacity of PE-ECC Members after Freeze-Thaw Cycles
摘要
Abstract
This study aims to investigate the effects of freeze-thaw cycles on load-bearing capacity of polyethylene fiber-reinforced engineered cementitious composites(PE-ECC)members.Through laboratory freeze-thaw cycle tests and post-freeze four-point bending tests,the failure evolution characteristics of PE-ECC beams under freeze-thaw action were investigated.The degradation patterns of their load-bearing capacity were analyzed using performance indicators such as stiffness,ductility index,and energy absorption capacity(EAC).The experimental results showed that:(1)the test beams maintained good structural integrity upon failure.Freeze-thaw cycles weakened the synergy between PE fibers and the matrix.With increasing freeze-thaw cycles,both the number of primary cracks and crack density decreased,and the cracks became more widely distributed.(2)The load-midspan deflection curves showed distinct elastic,yielding,and failure segments,which could be categorized into three loading stages:elastic stage,localized cracking stage in the tensile zone,and yielding failure stage.(3)Increasing PE fiber content resulted in a denser matrix structure,reduced the EAC loss,and enhanced load-bearing capacity after freeze-thaw cycles.(4)The strain distribution at the midspan cross-section of PE-ECC test beams after freeze-thaw cycles remained consistent with the plane section assumption.A calculation method for the load-bearing capacity of PE-ECC beams at each stage under bending load was proposed.These findings can provide a basis for the load-bearing capacity design of PE-ECC beams and their engineering applications in cold regions.关键词
PE-ECC/冻融循环/承载性能/破坏特征/受弯构件Key words
PE-ECC/freeze-thaw cycles/load-bearing capacity/failure characteristics/flexural mem-ber分类
交通工程引用本文复制引用
张志强,张康健,刘征..PE-ECC构件冻融循环后承载性能试验研究[J].铁道标准设计,2025,69(8):1-11,11.基金项目
国家自然科学基金项目(52378414) （52378414）
